Wakeboarding: The sport of wakeboarding has become increasingly popular in recent years. Wakeboarding typically involves using high speed boats equipped with a rope extending from the stem similar to those used in the sport of water skiing. Rather than skis, however, the wakeboarder's feet are normally strapped to a single, wider board, which allows the wakeboarder to skim sideways as well as forwards, while being pulled by the rope at somewhat slower speeds. As further distinguished from water skiing, the wakeboarder intentionally interacts with the boat's wake by using various elements of the wake to perform intricate maneuvers on and above the waves within the wake pattern. By crossing the wake transversely at high speeds, for example, a wakeboarder can utilize the first steep crest as a launch ramp to jump and cartwheel across the entire wake to land on the opposite side. By design, the wakeboard enables wakeboarders to skim over and across the wake, using the slope of the moving waves to perform maneuvers, such as jumps, ramps, turns, launches, etc.
A relatively long rope is typically attached at an elevated connection point at the boat's midpoint to enable skilled wakeboarders to maneuver freely behind the boat in both vertical and horizontal directions. With sufficient practice, skill and training, weight can be applied and shifted to adjust the wakeboard's position and angle relative to the moving waves, carving the board's edges into and across the waves, and using the rope for acceleration, guidance and control. For example, by cutting the wake board at an angle oblique to the direction of travel, the wakeboarder can `load` the rope, accelerate, hit the wake, and become airborne, achieving sufficient "hang time" and/or allowing the wakeboarder to perform desired acrobatic maneuvers.
An important element in the wakeboarder's repertory is the wake itself. For purposes of this invention, "wake" is defined as the wave pattern behind a moving boat that is generated by its passage through the water. This pattern normally arises from the "constructive" and "destructive" interference that occurs between divergent stem or bow waves and transverse body waves, whose size and character are related to the boat's length, shape, displacement, trim, and speed relative to the water. The quality and size of the wakes created by the boat significantly affect the wakeboarder's ability to achieve height on jumps and to perform the acrobatic maneuvers that are the essence of the sport.
Unfortunately for wakeboarders, conventional water ski boats are not designed to make waves but, rather, to minimize them in order to minimize power and to provide the smooth wake patterns that high speed skiing requires. Thus, the goal of traditional ski boat design is to lessen displacement, decrease drag, and enable the boat to travel faster with less energy. This is achieved, for example, by light displacement, straight after-buttock lines, a shallow-V bottom, and a bluff transom, so that the boat operates at high speed in a fully planing mode.
In order to generate an increase in wake size, wakeboarders have attempted to overcome the design objectives of traditional water ski boats by adding static ballast to the boat. Such ballast is usually in the form of water filled bags, concrete blocks, or other such weighted objects that disadvantageously occupy inboard passenger space. One other significant disadvantage to static ballast is that it can easily lead to an unsafe overload condition and scuttling.
Wake Surfing: In addition to wake boarding, a novelty sport, occasionally performed in the wave pattern behind a boat, is "wake surfing." This involves performing surfing maneuvers on a conventional surfboard in the wake of a boat, but without the benefit of a tow rope. Wake surfing maneuvers are entirely akin to those performed on natural ocean coastlines. The predominant factor that has limited the popularity and growth of wake surfing as a full-fledged sport has been the lack of boats capable of making good surfable waves at a safe distance behind the boat. More so than wakeboarding, wake surfing requires an even larger wave pattern of "surfable" quality.
Generation of sufficiently large (at least 3 feet [1 meter]), steep, surfable quality waves with a conventional ski boat is not currently possible. Even a ski boat ballasted for wakeboarding will only produce a wave of no more than about 18 inches (0.5 meter) in height. To create the maximum size wave typically involves a reduction in speed to what is technically termed the `hull speed` (to be discussed), which in the case of a standard water ski boat is approximately 10 mph or less. At such speeds, the waves created by the boat are typically within a few feet of the boat's transom, as well as the exhaust and propeller, making wake surfing using conventional ski-boats difficult to perform, unhealthy and dangerous. At a minimum, one would prefer waves behind the boat that are sufficiently steep and concave in shape to allow the performance of advanced surfing maneuvers, e.g., bottom turns, cutbacks, floaters, aerials, tailslides, etc., at least 15 feet (5 meters) away from the boat.
In view of the limitations of existing methods, as outlined above, the invention described below is concerned with boat activated wake enhancement methods and systems that can be incorporated with conventional high speed planing boats so that, when operated at designated speeds, they produce enhanced wave patterns, suitable in various embodiments to safely serve the respective sports of wakeboarding and wake surfing.